A model, structured by biological stages and with a cumulative development function was used to simulate biological stages of the population dynamics of the Mexican bean beetle, Epilachna varivestis Mulsant, under field conditions in the area of Texcoco, Mexico. The simulations were made to estimate the population dynamics of the Mexican bean beetle, depending on the time and their physiological age using the average of daily temperature values that occurred in the study area from July to October in the years 2007 and 2008, and the percentages of mortality observed in the field for each biological stage simulated for the insect. The simulations were compared with the population dynamics of the pest and its development times registered in the field, matched good estimations with a variation not greater, except for adults in 2008, than 7%.